A semiconductor device is formed by focusing a laser inside a wafer along the outer shape of a semiconductor element and then dividing and fragmenting the wafer into a plurality of semiconductor elements. Then, a sealing material is provided on each semiconductor element so as to tightly fix the semiconductor element and the sealing material for forming a semiconductor device. In such a semiconductor device, it is desirable to increase the strength of the semiconductor element while increasing the adhesion between the semiconductor element and the sealing material.